1. Field of the Invention
The present invention relates to a brush device for a motor such as a starter motor.
2. Discussion of Background
FIGS. 4 and 5 show a conventional brush holding device and its brush device used for a typical starter motor. In FIGS. 4 and 5, a reference numeral 1 designates a commutator for the starter motor, numerals 2a, 2b designate respectively positive side brushes and negative side brushes which are respectively held by holders so that they are urged toward the commutator 1 by means of respective brush springs 4 whereby an end of the respective brushes is in slide-contact with the commutator 1, and numeral 5 designates a pigtail for the positive side brushes 2a. The pigtail 5 is formed by firmly connecting an end of each of lead wires 5a connected to the brushes 2a and an end of lead wire 5b having the other end connected to a metallic terminal 6 at a firmly attached portion 5c. A numeral 7 designates a grommet made of rubber which is fitted to the lead wire 5b (FIG. 5). The grommet is fitted to the machine frame of the starter motor (not shown) to thereby prevent water and dust from entering in the starter motor through the pigtail portion. Numeral 8 designates lead wires for the negative side brushes 2b, which are connected to a base plate 9 of a metallic material to which the holders 3 are attached.
In the conventional brush device for a motor having the above-mentioned construction, the pigtail 5 is formed by firmly connecting the three lead wires 5a, 5b at portion 5c by welding or another suitable method. Accordingly, the operation for connecting is troublesome. Further, there is a problem that reliability to the connected portion is low since the three lead wires 5a, 5b are connected in one piece. There is another problem that when the lead wire 5b gets wet, water is apt to enter into the starter motor by the action of capillary tube because the lead wires 5a, 5b are generally made of twisted wires or woven wires. Further, since the grommet 7 is simply fitted to the lead wire 5b, the position of the grommet 7 on the lead wire 5b cannot be fixed. In particular, it is difficult to confirm a suitable position of the grommet 7 on the lead wire 5b after the brush device has been assembled in the starter motor.